EXPENSE-CONTRACT: V1

One extraction engine. Infinite destinations.

MailTract isn't just a web app; it's a versioned API contract. Approved, VAT-validated documents are pushed as draft expenses to any product that implements one small receiving endpoint.

The contract is deliberately small and strict. Every payload carries the exact multi-rate VAT breakdown, the supplier's VAT number, the source email reference, and a cryptographic file hash — so the receiving side can validate everything independently and deduplicate with certainty. MailTract never writes into another product's database; destinations create draft expenses and keep final control.

Versioning is explicit: within v1, changes are additive only. Consumers reject payloads they don't understand instead of misreading them.

Native destinations

Accountant (AccountantUK / KsięgowyUK) is live; VALEGRID Flow is next on the roadmap.

Deduplication built in

Document id + attachment SHA-256 travel with every payload — replays and forwards land once.

Phase 2

Embed MailTract's connect-mailbox and review UI natively in your own SaaS; the contract stays the boundary.

expense-contract v1 · one approved document
POST /api/integrations/mailtract/expenses
Authorization: Bearer <api-key>

{
  "contractVersion": "1.0",
  "documentType": "invoice",
  "issueDate": "2026-03-14",
  "supplierName": "ACME Supplies Ltd",
  "supplierVatNumber": "GB123456789",
  "invoiceNumber": "INV-2093",
  "currency": "GBP",
  "netAmount": 1033.33,
  "vatAmount": 206.67,
  "grossAmount": 1240.00,
  "vatBreakdown": [
    { "rate": 20, "net": 850.00, "vat": 170.00 },
    { "rate": 5,  "net": 120.00, "vat": 6.00 },
    { "rate": 0,  "net": 63.33,  "vat": 0.00 }
  ],
  "externalIds": { "mailtract": { "documentId": "doc_8f31…" } },
  "attachmentSha256": "9f2c…e1",
  "confidence": 0.97
}

Building a destination? The full contract specification ships in the MailTract repository (docs/expense-contract.md) — or create an account and connect a destination from Settings in minutes.

Ship expenses, not parsers.

Get API Access

🔒 Read-only access. GDPR compliant. We never send, alter, or delete your emails.